Figure 4. In vivo US imaging guided photothermal therapy.

(a) IR thermal images of tumor-bearing mice with and without PPyHMs injection exposed to the NIR laser at the power density of 0.64 W cm⁻² recorded at different time intervals. (b) contrast-enhanced ultrasonograms after the intratumoral injection of PPyHMs (0.2 mL, 2 mg mL⁻¹) into the mice from PPyHMs + laser group for visualization of the agent distribution to guide the following PTT (tumors are highlighted in the red circles). (c) The tumor growth curves of different groups of mice after PTT treatment. The tumor volumes were normalized to their initial sizes. (d) Representative photographs of mice bearing U87-MG tumors after various different treatments indicated. (e) H&E stained tumor slices collected from different groups of mice immediately after laser irradiation. The PPyHMs injected tumor was severely damaged after laser irradiation.